A uniform rod of length L and weight W is placed on a fulcrum a distance of 0.4L from the left end. On the left end is placed a mass of weight 2W and on the right end a vertical force F is applied to keep the system in balance. What are the magnitude and direction of the force F?
a. 7/6 W up
b. 4/3 W down
c. 7/6 W down
d. 4/3 W Up
Answer: c. 7/6 W down
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